A Polymer-Based Indicator for Detecting Dexamethasone in Herbal Medicine Using Polymethylmethacrylate (PMMA)

Abstract

Dexamethasone is a chemical drug that is usually added to herbal medicine because of its effects on pain relief, arthritis, anti-inflammation, etc. Chemical drugs should not be used in herbal medicine because uncontrolled consumption causes some side effects. A polymer-based indicator was developed to detect dexamethasone in herbal medicine samples in a fast and simple way compared to instrumental analysis. The indicator strips were made by mixing polymethylmethacrylate (PMMA) polymer with sulfuric acid (H2SO4) as a reagent. When reacting with dexamethasone, H2SO4 can cause the color to change into a specific light pink-purple color. Indicator strips were prepared with a composition of 5% PMMA in ethyl acetate:H2SO4 (9:1) by using the reagent blending method. The indicator strips showed a pink-purple color when they were applied to a positive herb containing dexamethasone. The indicator strips could selectively detect dexamethasone rather than other active substances that are often found in herbal medicine. These indicator strips could also detect dexamethasone with the smallest detection limit of 13.13 ppm, and they had a stability of up to 36 days. Detection was carried out in real samples to show the performance of the indicator strips. The result showed that of nine samples, five were confirmed to contain dexamethasone. These results showed a good agreement with the results of thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). According to the result, these indicator strips provide a simple and applicable method for on-site analysis to detect dexamethasone in samples.

High-Density Au Anchored to Ti3C2-Based Colorimetric-Fluorescence Dual-Mode Lateral Flow Immunoassay for All-Domain-Enhanced Performance and Signal Intercalibration

“…Ti 3 C 2 @Au was synthesized by a simple one-pot self-reduction method with a high molar extinction coefficient, strong fluorescence quenching ability, ultrahigh dispersibility, and good biocompatibility, this enabled efficient and sensitive detection at low antibody (Ab) levels. DXMS is an artificially synthesized glucocorticoid with pharmacological effects such as anti-inflammatory, antitoxic, antiallergic, and antirheumatic, which is commonly used in veterinary clinics for the treatment of metabolic diseases in female animals. , Long-term consumption of animal products containing excessive DXMS will cause hormone metabolism disorders in the human body, resulting in osteoporosis, growth retardation, and in serious cases, diabetes, hypertension, myocardial infarction, peptic ulcers, and other symptoms, which are detrimental to human health. − This immunosensor took DXMS as the research model and realized the mutual calibration of the two signals through the combination of “turn-off” and “turn-on” modes, contributing to higher reliability. It is believed that this study can provide more references for the subsequent application of MXene-based biosensors to food safety.…”